#include <iostream>
#include <cstdio>
#include <algorithm>
#include <cmath>

using namespace std;

int main() {
    #ifndef ONLINE_JUDGE
        freopen("input", "rt", stdin);
        freopen("output", "wt", stdout);
    #endif

    double g = 9.81;
    double l, h, nu;
    cin >> l >> h >> nu;
    l /= 100;
    h /= 100;
    nu /= 60;
    double t = sqrt(2.0*(h-l/2)/g);
    if ((int)((4*nu)*t) % 4 == 0 || (int)((4*nu)*t) % 4 == 3)
        cout << "butter";
    else
        cout << "bread";

    return 0;
}
